Hot take but I think Davies Killed Who in his first run and the show's been spinning out since then.
The show became too focused on Tennant, who became too powerful & since then it's been tough to fix the scaling problems that left behind (if he can threaten anyone into backing down how do you write a good badie?), I also think Davies tendency to run back to Tennant every chance he gets is pretty annoying.
That's not say it hasn't been a great show since then, it's just very difficult to maintain tension when you have elevated the main character(s) to literal gods, see also Stargate.
I mean I love the show and thought Gatwa & Whittaker were good doctors (except for the whole Flux thing), but each new doctor is either disliked for not being Tennant or for being too "woke".